michigan. Betty liu, thank you so much. We're going to get to the whitey bulger case. A possible witness for the prosecution who was ready to testify was found dead. The causes have still being investigated. And abc's ron claiborne has more on this story. Reporter: This morning, a classic mobster mystery. All police know is that this man, stephen rakes, was found dead on the side of the road in a boston suburb. No wallet. No identification. No signs of trauma. Police say it appeared it could have been suicide. Friends say it's impossible. I don't. You don't think so? He was a happy guy. Reporter: More fuel for suspicion, rakes has been slated to testify against james "whitey" bulger, the former ruthless boss of the boston mob. He probably sleeps in an ice chest. Reporter: That was a few days ago. Rakes was expected to take the stand to say that bulger had threatened him in front of his daughter, until he, rakes, let him take over his south boston liquor store and turn it into his alleged gang headquarters. Looking forward to court to testify. Reporter: On thursday, prosecutors called their star witness, steven the rifleman remy, who admitted he was bulger's pal and partner in organized crime. The two later had a falling out and now are bitter enemies. Today, the focus for many here is on the witness that was never called to testify and will now never take the stand. The bulger trial resumes later today, going into all the gory details about how he and bulger allegedly ran their criminal empire. Yesterday, that session ended with the two men standing and glaring one another, and mouthing expletives that were not hard to decode.

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